Detection of spin polarization in quantum point contacts
نویسندگان
چکیده
We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the low density regime, when the conductance of a point contact is tuned to <2e2/h. Polarization is stronger in samples with a well defined ‘0.7 structure’. (Some figures in this article are in colour only in the electronic version)
منابع مشابه
Spontaneous spin polarization in quantum point contacts.
We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the low-density regime, when the conductance of a point contact is tuned to < 2e2/h. Polarization is stronger in samples with a well-defined "0.7 structure."
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